A group of notorious Chinese hackers successfully pulled a con job by staging a perfect plot to fool top executives at the Indian arm of Italian company Tecnimont SpA. The con job is one of India's biggest cyber heists valued at a whopping Rs 130 crore ($18.6 million), which is the amount hackers stole from the company.

While the criminals remain at large, an official investigation has been initiated by the Mumbai Police's cybercrime unit in tandem with a white-collar criminal law and fraud investigating firm MZM Legal. Tecnimont SpA, which specialises in engineering, energy and chemicals, conducted a forensic investigation and also hired a Mumbai-based law firm and Manhattan-based security firm, Kroll, to look into the matter, ET reported.

"This is a very serious case of electronic fraud by a very highly skilled group of international criminals working with high-end technology. We are working with the Mumbai Cyber Cell to investigate the matter and get to the bottom of this," Zulfiquar Memon, managing partner of MZM Legal, said in a statement.

How did the heist take place?

It all started with emails sent to the India chief of Tecnimont Pvt. Ltd. The hackers pretended to be the group CEO Pierroberto Folgiero by using an email account that's deceptively similar to the real one.

(PICTURE FOR REPRESENTATION ONLY) Hackers steal Rs 130 crore from an Italian-based firm in IndiaReuters

The skilled criminals staged the entire operation to be "secretive" and "highly confidential," which made the victims involved in the con subject to discretion. By hosting series of conference calls to discuss a fake acquisition in China by involving various people for the roles of group CEO, a well-known Switzerland-based lawyer and other senior execs of the company, the hackers did everything to make this con appear as real as it can be.

Finally, towards closing the deal, hackers convinced the India chief of the company to transfer the money. By flagging regulatory issues, the hackers then influenced the India head to transfer a total of $18.6 million from India to the banks in Hong Kong.

The total sum was transferred in three tranches - $5.6 million, $9.4 million and $3.6 million. While the hackers attempted for a fourth transfer, the con had been discovered by then. According to the report, Tecnimont SpA chairman Franco Ghiringhelli had visited India in December when the fraud came to light.

The company didn't label the professional heist as cyber-attack but a fraud.

The investigations have revealed that the bank accounts where the money was transferred was opened using fake documents and the money had been withdrawn within minutes. The conference calls had fraudulent IDs and the top Swiss lawyer, Luigi Corradi, who has also been named in the complaint, doesn't really exist. It appears the hackers used the name of a well-known Italian engineer and teacher who died in 1921.

The police complaint also revealed that the company head in India alongside the chief of accounts and finance have been sacked following the incident.